Electroluminescent arrangements using blend systems

ABSTRACT

The invention concerns electroluminescent arrangements composed of a substrate, an anode, an electroluminescent element and a cathode, at least one of the two electrodes being transparent in the visible spectrum range. The electroluminescent electrode can contain the following components in sequence: an electroluminescent, holeinjecting, holetransporting zone, an electrontransporting zone and an electron-injecting zone. The invention is characterized in that the holeinjecting and holetransporting zone contains an optionally substituted tris 1,3,5(aminophenyl) benzene compound A or a mixture thereof, and the electroluminescent element optionally contains a further functionalized compound selected from the group comprising holetransporting materials, a luminescent material B and optionally electrontransporting materials. In addition to component A, the holeinjecting and holetransporting zone can comprise one a plurality of further holetransporting compounds. At least one zone is present, individual zones can be omitted and the zone (s) present can assume a plurality of functions.

[0001] An electroluminescent (EL) arrangement is characterised in thatit emits light with current flow on the application of an electricalvoltage. In technology such arrangements have for a long time been knownby the term “light diodes” (LEDs =light-emitting diodes). The emissionof light takes place owing to the fact that positive charges (holes) andnegative charges (electrons) recombine with the emission of light.

[0002] Nowadays mainly inorganic semiconductors, such as galliumarsenide, are used in the development of light-emitting components forelectronics or photonics. Display elements in the form of dots can beproduced from such substances. Large-surface arrangements are notpossible.

[0003] Besides the semiconductor light diodes, electroluminescentarrangements based on vapour-deposited low-molecular organic compoundsare known (U.S. Pat. No. 4 539 507, U.S. Pat. No. 4 769 262, U.S. Pat.No. 5 077 142, EP-A 406 762, EP-A 278 758, EP-A 278 757).

[0004] Polymers, such as poly(p-phenylenes) andpoly(p-phenylenevinylenes) (PPV) are also reported as beingelectroluminescent polymers: G. Leising et al., Adv. Mater. 4 (1992) No.1; Friend et al., J. Chem. Soc., Chem. Commun. 32 (1992); Saito et al.,Polymer, 1990, Vol. 31, 1137; Friend et al., Physical Review B, Vol. 42,No. 18, 11670 or WO 90/13148. Further examples of PPV inelectroluminescent displays are described in EP-A 443 861, WO-A-9203490and 92003491.

[0005] EP-A 0 294 061 introduces an optical modulator based onpolyacetylene.

[0006] For the production of flexible polymer LEDs, Heeger et al. haveproposed soluble conjugated PPV-derivatives (WO 92/16023).

[0007] Polymer blends of varying composition are also known: M Stolkaet. al., Pure 7 Appt. Chem., Vol. 67, No. 1, pp 175-182, 1995; H.Bässler et al., Adv. Mater. 1995, 7, No. 6, 551; K. Nagaietal., Appl.Phys. Lett. 67 (16) 1995, 2281; EP-A 532 798.

[0008] The organic EL arrangements generally contain one or more layersof organic charge-transport compounds. The fundamental structure, inorder of layers, is as follows:

[0009] 1. carrier, substrate

[0010] 2. basis electrode

[0011] 3. hole-injecting layer

[0012] 4. hole-transporting layer

[0013] 5. light-emitting layer

[0014] 6. electron-transporting layer

[0015] 7. electron-injecting layer

[0016] 8. top electrodes

[0017] 9. contacts

[0018] 10. case, encapsulation.

[0019] Layers 3 to 7 constitute the electroluminescent element.

[0020] This structure represents the most universal case and can besimplified by omitting individual layers, so that one layer assumesseveral functions. In the simplest case, an EL arrangement consists oftwo electrodes, between which there is an organic layer which fulfilsall the functions, including that of light emission. Such systems aredescribed, for example, in the Application WO 90/13148, based onpoly(p-phenylenevinyls).

[0021] Multilayered systems can be built up by vapour-depositionprocesses, during which the layers are successively applied from thevapour phase, or by casting processes. Casting processes are preferred,because of the higher processing speeds. Admittedly, the partialsolution of an already applied layer in the course of covering it withthe next layer can be a difficulty in certain cases.

[0022] The object of the present invention is to provideelectroluminescent arrangements which have high luminance and in whichthe mixture to be applied can be applied by casting.

[0023] It has been found that these requirements are met byelectroluminescent arrangements containing the blend system specifiedbelow. In the following, the term “zone” is to be regarded as equivalentto “layer”. The present invention accordingly provideselectroluminescent arrangements containing a substrate, an anode, anelectroluminescent element and a cathode, wherein at least one of thetwo electrodes is transparent in the visible spectral range and theelectroluminescent element can contain, in order: a hole-injecting zone,hole-transporting zone, electroluminescent zone, electron-transportingzone and/or an electron-injecting zone, characterised in that thehole-injecting and/or hole-transporting zone is an optionallysubstituted tris-1,3,5-(aminophenyl) benzene compound A) or a mixturethereof and the electroluminescent element contains optionally a furtherfunctionalised compound selected from among the hole-transportingmaterials, a luminescent material B) and optionallyelectron-transporting materials, and the hole-injecting andhole-transporting zone can contain one or more further hole-transportingcompounds in addition to component A), at least one zone being present,individual zones can be omitted and the zone(s) present can assume oneor more functions.

[0024] A zone can assume several functions; that is to say, a zone cancontain, for example, hole-injecting, hole-transporting,electroluminescent, electron-injecting and/or electron-transportingsubstances.

[0025] The electroluminescent element can also contain one or moretransparent polymeric binders C.

[0026] The optionally substituted tris-1,3,5-(aminophenyl)benzenecompound A) represents an aromatic tertiary amino compound correspondingto the general formula (I)

[0027] wherein

[0028] R² represents hydrogen, optionally substituted alkyl or halogen,

[0029] R³ and R⁴, independently of one another, represent optionallysubstituted C₁—C₁₀-alkyl, alkoxycarbonyl-substituted Cl—Clo-alkyl,optionally substituted aryl, optionally substituted aralkyl oroptionally substituted cycloalkyl.

[0030] R³ and R⁴, independently of one another, represent preferablyC₁—C₆-alkyl, in particular methyl, ethyl, n- or isopropyl, n-, iso-,sec.- or tert.-butyl, C₁—C₄-alkoxycarbonyl-C₁—C₆-alkyl, such as, forexample, methoxy-, ethoxy-, propoxy-, butoxycarbonyl-C₁—C₄-alkyl; alsophenyl-C₁—C₄-alkyl, naphthyl-C₁—C₄-alkyl, cyclopentyl, cyclohexyl,phenyl or naphthyl, in each case optionally substituted by C₁—C₄-alkyland/or C₁—C₄-alkoxy.

[0031] Particularly preferably R³ and R⁴, independently of one another,represent unsubstituted phenyl or naphthyl, or phenyl or naphthyl eachsingly to triply substituted by methyl, ethyl, n-, isopropyl, methoxy,ethoxy, n- and/or isopropoxy.

[0032] R² represents preferably hydrogen, C₁—C₆-alkyl, such as, forexample, methyl, ethyl, n- or isopropyl, n-, iso-, sec.- or tert.-butylor chlorine.

[0033] Compounds such as these and their preparation are described inU.S. Pat. No. 4 923 774 for use in electrophotography, and the patentjust cited is herewith expressly incorporated as part of the presentdescription (“incorporated by reference”). The tris(nitrophenyl)compound can be converted into the tris(aminophenyl) compound, forexample, by generally known catalytic hydrogenation, for instance, inthe presence of Raney nickel (Houben-Weyl 4/1 C, 14-102, Ullmann (4) 13,135-148). The amino compound is reacted with substituted halobenzenes inthe generally known way.

[0034] The following compounds, wherein the substitution on the phenylring can be ortho, meta and/or para to the amine nitrogen, are given byway of example.

[0035] In addition to component A), further hole conductors, forexample, in the form of a mixture with component A), may optionally beused for the construction of the electroluminescent element. These mayon the one hand be one or more compounds corresponding to formula (I),also including mixtures of isomers; on the other hand they may also bemixtures of hole-transporting compounds with compounds ofA)—corresponding to the general formula (I)—of different structure.

[0036] A list of possible hole-injecting and hole-conducting materialsis given in EP-A 532 798.

[0037] In the case of mixtures of component A), the compounds may beused in any proportion between 0 and 100 wt. % (based on the mixtureA)). In a preferred embodiment, 1 to 99 wt. % and 99 to 1 wt. %,particularly preferably 5 to 95 wt. % and 95 to 5 wt. %, are used. Inanother preferred embodiment, 30 to 70 wt. % and 70 to 30 wt. % areused.

[0038] Examples which may be given are:

[0039] anthracene compounds, for example, 2,6,9,10-tetraisopropoxyanthracene; oxadiazole compounds, for example,2,5-bis(4-diethylaminophenyl)-1,3,4-oxadiazole; triphenylaminecompounds, for example,N,N′-diphenyl-N,N′-di(3-methylphenyl)-1,1′-biphenyl-4,4′-diamine;aromatic tertiary amines, for example, N-phenylcarbaz-ole,N-isopropylcarbazole and compounds which can be used inhole-transporting layers, such as are described in the Japanese PatentApplication Offenlegungsnr. 62-264 692; also pyrazoline compounds, forexample,1-phenyl-3-(p-diethylamino-styryl)-5-(p-diethylaminophenyl)-2-pyrazoline;styryl compounds, for example, 9-(p-diethylaminostyryl) anthracene;hydrazone compounds, for example, bis(4-dimethylamino-2-methylphenyl)phenylmethane; stilbene compounds, for example,α-(4-methoxyphenyl)-4-N,N-diphenylamino(4′-methoxy)stilbene; enaminecompounds, for example,1,1-(4,4′-diethoxyphenyl)-N,N-(4,4′-dimethoxyphenyl)-enamine; metalphthalocyanines or nonmetal phthalocyanines and porphyrin compounds.

[0040] Triphenylamine compounds and/or aromatic tertiary amines arepreferred, the compounds given above as examples being particularlypreferred.

[0041] The following are examples of materials which havehole-conducting properties and can be used together with component A) ina mixture.

[0042] These and other examples are described in J. Phys. Chem. 1993,97, 6240-6248 and Appl. Phys. Lett., Vol. 66, No. 20, 2679-2681. BinderC) represents polymers and/or copolymers such as, for example,polycarbonates, polyester carbonates, copolymers of styrene such as SANor styrene acrylates, polysulfones, polymers based on monomerscontaining vinyl groups such as, for example, poly(meth)acrylates,polyvinylpyrrolidone, polyvinylcarbazole, vinyl acetate polymers andcopolymers and vinyl alcohol polymers and copolymers, polyolefins,cyclic olefinic copolymers, phenoxy resins et cetera. Mixtures ofdifferent polymers can also be used. The polymeric binders C) havemolecular weights of from 10,000 to 2,000,000 g/mol., are soluble andfilm-forming and are transparent in the visible spectral range. They aredescribed, for example, in Encyclopedia of Polymer Science andEngineering, 2nd Edition, A. Wiley Interscience. They are conventionallyused in a quantity of up to 95 wt.%, preferably up to 80 wt.%, based onthe total weight of A) and B).

[0043] Component B) represents a compound corresponding to the generalformula (II)

[0044] wherein

[0045] Me represents a metal,

[0046] m is a number from 1 to 3 and

[0047] Z independently in both forms represents atoms which complete anucleus which consists of at least 2 condensed rings.

[0048] In general monovalent, divalent or trivalent metals which areknown to form chelates can be used.

[0049] The metal can be a monovalent, divalent or trivalent metal, forexample, lithium, sodium, potassium, magnesium, calcium, boron oraluminium.

[0050] Z completes a heterocyclic molecular unit which consists of atleast two condensed rings, of which one is an azole or azine ring, andfurther additional aliphatic or aromatic rings can be bonded to the twofused rings.

[0051] Suitable examples of component B) are the oxine complexes(8-hydroxyquinoline complexes) of Al³⁺, Mg²⁺, In³⁺, Ga³⁺, Zn²⁺, Be²⁺,Li⁺, Ca²⁺, Na⁺ or aluminium tris(5-methyloxine) R and galliumtris(5-chloroquinoline). Complexes with rare earth metals can also beused.

[0052] Examples of component B) are

[0053] Inq₃, Gaq₃, Znq₂, Beq₂, Mgq2,

[0054] or Al(qa)₃, Ga(qa)₃, In(qa)₃, Zn(qa)₂, Be(qa)₂, Mg(qa)₂, wherein

[0055] One or more component B) compounds can be used.

[0056] The compounds or the oxine complexes of component B) aregenerally known and can be prepared by known methods (cf. for example,U.S. Pat. No. 4 769 292).

[0057] The electroluminescent arrangements according to the inventionare characterised by having a light-emitting layer which contains amixture of the components A) and B) in optionally a transparent binderC). Here the weight ratio of A) and B) to one another is variablyadjustable.

[0058] The percentage by weight of the sum of the percentages by weightof A) and B) in the polymeric binder is in the range of from 0.2 to 98wt.%, preferably from 2 to 95 wt.%, particularly preferably from 10 to90 wt.%, most preferably 10 to 85 wt.%.

[0059] The weight ratio A:B of components A) and B) is between 0.05 and20, preferably 0.2 and 10 and particularly preferably between 0.3 and 8,in particular 0.3 and 7. Components A) and B) may consist either of onecomponent or of a mixture of components of any composition.

[0060] To produce the layer, components A), B) and optionally C) aredissolved in a suitable solvent and by means of casting, knife-coatingor spin-coating are applied to a suitable support. This can, forexample, be glass or a plastics material provided with a transparentelectrode. The plastics material used can be, for example, a sheet ofpolycarbonate, polyester such as polyethylene terephthalate orpolyethylene naphthalate, polysulfone or polyimide.

[0061] Suitable transparent electrodes are

[0062] a) metal oxides, for example, indium-tin oxide (ITO), tin oxide(NESA), zinc oxide, doped tin oxide, doped zinc oxide, et cetera,

[0063] b) semi-transparent metal films, for example, Au, Pt, Ag, Cu, etcetera,

[0064] c) conductive polymer films such as polyanilines, polythiophenes,et cetera.

[0065] The metal oxide electrodes and the semi-transparent metal filmelectrodes are applied in a thin layer by techniques such as vapourdeposition, sputtering, platinising, et cetera. The conductive polymerfilms are applied from solution by techniques such as spin-coating,casting, knife-coating, et cetera.

[0066] The thickness of the transparent electrodes is 3 nm up to aboutseveral μm, preferably 10 mn to 500 nm.

[0067] The electroluminescent layer is applied as a thin film directlyto the transparent electrode or to an optionally presentcharge-transporting layer. The thickness of the film is 10 to 500 mn,preferably 20 to 400 mn, particularly preferably 50 to 250 nm.

[0068] An additional charge-transporting layer can be applied to theelectroluminescent layer before a counterelectrode is applied.

[0069] A list of suitable charge-transporting intermediate layers, whichcan be hole-conducting and/or electron-conducting materials and can bein polymeric or low-molecular form, optionally as a blend, is given inEP-A 532 798. Specially substituted polythiophenes possessinghole-transporting properties are particularly suitable. They aredescribed, for example, in EP-A 686 662.

[0070] The content of low-molecular hole conductors in a polymericbinder is variable within the range of 2 to 97 wt. %; the content ispreferably 5 to 95 wt. %, particularly preferably 10 to 90 wt. %, inparticular 10 to 85 wt. %. The hole-injecting and hole-conducting zonescan be deposited by various methods.

[0071] Film-forming hole conductors can also be used in pure form(100%). The hole-injecting or hole-conducting zone may optionally alsocontain a proportion of an electroluminescent substance.

[0072] Blends which consist exclusively of low-molecular compounds canbe vapour-deposited; soluble and film-forming blends, which in additionto low-molecular compounds may also (not necessarily) contain a binderC), can be deposited from a solution, for example, by means ofspin-coating, casting, knife-coating.

[0073] It is also possible to apply emitting and/or electron-conductingsubstances in a separate layer to the hole-conducting layer containingcomponent A). In this case an emitting substance (“dopant”) can also beadded to the layer containing component A) and in addition anelectron-conducting substance can be applied. An electroluminescentsubstance can also be added to the electron-injecting orelectron-conducting layer.

[0074] The content of low-molecular electron conductors in a polymericbinder is variable within the range of 2 to 95 wt.%; the content ispreferably 5 to 90 wt. %, particularly preferably 10 to 85 wt. %.Film-forming electron conductors can also be used in pure form (100%).

[0075] The counterelectrode is composed of a conductive substance, whichcan be transparent. Preferred substances are metals, for example, Al,Au, Ag, Mg, In, et cetera, or alloys and oxides of these, which can beapplied by techniques such as vapour-deposition, sputtering,platinising.

[0076] The arrangement according to the invention is brought intocontact with the two electrodes by means of two electrical leads (forexample, metal wires).

[0077] On the application of a direct-current voltage in the range of0.1 to 100 volt, the arrangements emit light having a wavelength of 200to 2000 nm. It displays luminescence in the range of 200 to 2000 nm.

[0078] The arrangements according to the invention are suitable for theproduction of units for illumination and for data presentation.

EXAMPLE 1

[0079] Electroluminescent arrangement based on a blend system consistingof

[0080] A:

[0081] B:

[0082] 8-hydroxyquinoline aluminium salt (aluminium oxinate)

[0083] C: Polyvinylcarbazole (Luvican EP, BASF AG, Ludwigshafen,Germany)

[0084] A 1% solution consisting of 1 part by weight A, 1 part by weightB and 4 parts by weight C in dichloroethane is spread out on a glassplate coated with ITO (Baltracon 255 from the firm Balzers) by means ofa commercial spin-coater at a rate of rotation of 400/min.

[0085] The layer thickness is 100 nm.

[0086] As counterelectrode, Mg/Ag in the ratio of 10:1 is applied bythermal codeposition.

[0087] After contacting and application of an electrical field, fromabout 7 V the arrangement shows visually detectable electroluminescencein the green spectral range. The luminous intensity is 355 cd/m² at acurrent of 19 mA/cm² and a voltage of 16 V.

EXAMPLE 2

[0088] Electroluminescent arrangement based on a blend system consistingof:

[0089] A) 1 part by weight of the following compound:

[0090] B) 1 part by weight Alq₃

[0091] C) 4 parts by weight polyvinylcarbazole (Luvican EP, BASF AG,Ludwigshafen, Germany).

[0092] Layer production and contacting are carried out as in Example 1.The luminous intensity at an applied voltage of 16 V and a current of22.6 mA/cm² is 455 cd/M².

EXAMPLE 3

[0093] Electroluminescent arrangement based on a blend system consistingof:

[0094] A) 1 part by weight of the following compound:

[0095] B) 1 part by weight Alq₃

[0096] C) 4 parts by weight polyvinylcarbazole (Luvican EP, BASF AG,Ludwigshafen, Germany).

[0097] Layer production and contacting are carried out as in Example 1.The luminous intensity at an applied voltage of 20 V and a current of18.7 mA/cm² is 310 cd/m².

EXAMPLE 4

[0098] Electroluminescent arrangement based on a blend system consistingof:

[0099] A) 1 part by weight of the following compound:

[0100] B) 1 part by weight Alq3

[0101] C) 4 parts by weight polyvinylcarbazole (Luvican EP, BASF AG,Ludwigshafen, Germany).

[0102] Layer production and contacting are carried out as in Example 1.The luminous intensity at an applied voltage of 15 V and a current of17.6 mA/cm² is 250 cd/m².

EXAMPLE 5

[0103] Electroluminescent arrangement containing a hole-conducting layerbased on

[0104] A) a mixture of the hole conductors (weight ratio 1:1)

[0105] B) an electron-conducting or emitting layer based on

[0106] 8-hydroxyquinoline aluminium salt (aluminium oxinate) and

[0107] C) polystyrene (Aldrich, 89555 Steinheim, Germany, productnumber: 18,242-7)

[0108] A 1% solution, consisting of 1 part by weight A, 1 part by weightB and 1 part by weight C in dichloroethane is spread out on a glassplate coated with ITO (Baltracon 255 from the firm Balzers) by means ofa commercial spin-coater at a rate of rotation of 800/min. Anelectron-conducting or emitting layer, consisting of Alq₃, isvapour-deposited at 10⁻⁶ mbar onto this hole-conducting layer. The layerthickness is approximately 60 nm.

[0109] As counterelectrode, an Mg/Ag alloy in the ratio of 10:1 isapplied by thermal codeposition. The system emits green light. The diodeemits green light at a voltage of 3 V and above.

EXAMPLE 6

[0110] Electroluminescent arrangement based on component A:

[0111] A 1.5% solution of A) in chloroform is spread out on a glassplate coated with ITO (Baltracon 255 from the firm Balzers) by means ofa commercial spin-coater at a rate of rotation of 1000/min. The layerthickness is 120 nm.

[0112] As counterelectrode, Al is applied by thermal vaporisation.

[0113] After contacting and application of an electrical field, from 8 Velectroluminescence can be detected by means of an Si photodiode. At avoltage of 20 V, a current of 25 mA/cm² flows and the luminance is 2cd/m². The colour of the electroluminescence is blue.

1. Electroluminescent arrangements, composed of a substrate, an anode,an electroluminescent element and a cathode, wherein at least one of thetwo electrodes is transparent in the visible spectral range and theelectroluminescent electrode can contain, in order: a hole-injectingzone, hole-transporting zone, electroluminescent zone,electron-transporting zone and/or an electron-injecting zone,characterised in that the hole-injecting and/or hole-transporting zoneis an optionally substituted tris- 1,3,5-(aminophenyl)benzene compoundA) or a mixture thereof and the electroluminescent element containsoptionally a further finctionalised compound selected from among thehole-transporting materials, a luminescent material B) and optionallyelectron-transporting materials, and the hole-injecting andhole-transporting zone can contain one or more further hole-transportingcompounds in addition to component A), at least one zone being present,individual zones can be omitted and the zone(s) present can assume oneor more functions.
 2. Electroluminescent arrangements according to claim1, characterised in that the electroluminescent element contains atransparent polymeric binder C).
 3. Electroluminescent arrangementsaccording to claim 1, wherein the compound A) is an aromatic tertiaryamino compound corresponding to the general formula (I)

wherein R² represents hydrogen, optionally substituted alkyl or halogen,R³ and R⁴, independently of one another, represent optionallysubstituted C₁—C₁₀-alkyl alkoxycarbonyl-substituted C₁—C₁₀-alkyl,optionally substituted aryl, optionally substituted aralkyl oroptionally substituted cycloalkyl, or a mixture of compoundscorresponding to formula (I) with hole-transporting compounds which havea structure different from formula (1).
 4. Electroluminescentarrangement according to claim 1, wherein in formula (I) R² representshydrogen or C₁—C₆-alkyl, R³ and R⁴, independently of one another,represent C₁—C₆-alkyl, C₁—C₄-alkoxycarbonyl-C₁—C₆-alkyl; phenyl,naphthyl, phenyl-C₁—C₄-alkyl, naphthyl-C₁—C₄-alkyl, cyclopentyl orcyclohexyl, in each case optionally substituted by C₁—C₄-alkyl and/orC₁—C₄-alkoxy.
 5. Electroluminescent arrangement according to claim 1,wherein the tertiary amine A) is selected from the following compounds:


6. Electroluminescent arrangement according to claim 1, whereincomponent B) is a compound corresponding to the general formula (11)

wherein Me represents a metal, m is a number from 1 to 3 and Zindependently in both forms represents atoms which complete a nucleuswhich consists of at least 2 condensed rings.
 7. Electroluminescentarrangement according to claim 6, wherein Me represents monovalent,divalent or trivalent metal which forms chelates.
 8. Electroluminescentarrangement according to claim 1, wherein the transparent binder isselected from among polycarbonates, polyester carbonates, copolymers ofstyrene such as SAN or styrene acrylates, polysulfones, polymers basedon monomers containing vinyl groups, polyolefins, cyclic olefiniccopolymers, phenoxy resins.
 9. Electroluminescent arrangement accordingto claim 6, wherein component B) is selected from oxine complexes(8-hydroxyquinoline complexes) of Al³⁺, Mg²⁺, In³⁺, Li⁺, Ca²⁺, Na⁺ oraluminium tris(5-methyloxine)_(R) and gallium tris(5-chloroquinoline) orrare earth metal complexes.
 10. Electroluminescent arrangement accordingto claim 1, wherein the percentage by weight of the sum of thepercentages by weight of A) and B) in the polymeric binder is in therange of from 0.2 to 98 wt. % (based on 100 wt. % of A) +B) +C)) and theweight ratio A):B) of components A)and B) is between 0.05 and
 20. 11.Electroluminescent arrangement according to claims 1 to 10, wherein theelectroluminescent element contains a further charge-transportingsubstance selected from the hole-conducting and/or electron-conductingmaterials.
 12. Electroluminescent arrangement according to claims 1 to11, wherein the electroluminescent element consists of a single-layersystem.
 13. Electroluminescent arrangement according to claims 1 to 12,wherein the electroluminescent element consists of only one zone, whichcontains an optionally substituted tris-1,3,5-(aminophenyl)benzenecompound, 8-hydroxyquinoline ammonium salt (aluminium oxilate) andpolyvinylcarbazole.
 14. Use of the electroluminescent arrangementaccording to claims 1 to 13 for illumination/background illumination,data presentation and for the construction of segment or matrixdisplays.